Spring element



May 5, 1936. ca. PlELSTlCK SPRING ELEMENT 7 Filed Feb; 21, 1954 Patented May 5, 1936 UNITED ,STATES PATENT OFFICE] SPRING ELEMENT Application February-21, 1934, Serial No. 712,334

In Germany February 27, 1933 6 Claims. (Cl. 2671) This invention relates to spring. elements. One object of the invention is the provision of a spring element adapted for use in shock absorbers, flexible couplings and in, many .other places, and embodying a series of nested spring shells of simple construction and cooperatively arranged to yieldingly transmit a force from one point to another.

Another object of the invention is the provision of a spring element embodying a series of nested spring :shells substantially c-shaped in cross-section and cooperating with an inner core the curved surface of which has a smaller radius than the normal inside radius of curvature ofthe inner shell. e

Other objects and advantages of the invention will be apparent from the following description, the appended claims and the accompanying drawing, .in which,--

Fig. 1 is a side elevation of a spring element embodying the present invention;

Fig. 2 is a central transverse section through the spring element;

Fig. 3 is an end view of a spring element having spring shells of graduated thickness, the core being shown in section; and

Fig. 4 is an end view corresponding to Fig. 3 but showing a modified form of construction in which groups of spring shells are 01' graduated strength.

Referring more particularly to the drawing by reference letters, Figs. 1 and 2 show a spring element comprising a series of concentrically telescoped, or nested, metal spring shells each side and thus substantially C-shaped in crosssection. The several spring shells a, b, c, and d are arranged or curved around a core member e which has a projecting rib f extending into the space 9 between the opposed side .edge sof the several springshells. The radius of curvature from a line of contact. When a force is exerted.

tending to compress the spring shells and bring their adjacent edges closer together the inner spring shell a is wrapped to a substantial extent around the core so that the resistance to spring flexure is gradually increased as the load is increased, and the flexibility of the spring is-maintainedwithinits elastic limit.- The elasticity of the spring element can be made any desired being longitudinally slotted along one complete value, depending upon the number of spring shells employed.

Inasmuch as the rib j projects through the longitudinal slot or open side of the several shells,

the latter are prevented from excessive relative shells can thus be uniformly stressed and an applied forcedivided among the several shells in accordance with their respective capacities.

The several spring shells a, b,'c, and d are preferably made frombent and hardened metal ,blanks, and'may be of varying strength or flexibility. The thickness of the material of the successive shells may decrease toward the center of the spring element in accordance with the distance of the spring shell from the central axisof. the element. Thus the innermost shell may be of considerably smaller thickness because it has the shortest leverage for the transmission of forces,- that is during compression the innermost shell is required to bend around a. smaller radius than an outer shell. The. thicknesses of the outer shells are increased in proportion to their radius of curvature so that all shells-may be uniformlystressed. Thus as shown in- Fig. 3 the thickness of the several shells a, b, c, d, h. and i graduallyvaries so as to increase by successive steps from the innermost shell to' the outermost shell'in proportion to the radius of the shells.

In Fig. 4 a construction is known in which the thickness of the group of spring shells his the same, but the thickness of the-shells k is greater most group of shells 12 having still smaller thickness in proportion to the radius of curvature. Such a constructionis particularly desirable where a large number of spring shells must be employed, as a comparatively few different thickness'es of material may be utilized instead of formerly employed coil, spiral or leaf springs. A spring element for'example may be inserted in a longitudinal bore somewhat smaller in diameter than the normal outside expanded diamslowly graduating the thickness'from one individual shell to the next.

Spring elements of the character herein set F forth may be used in a great many places which eter of the unstressed spring and provided in a plurality of relatively rotatable elements of a coupling so as to yieldinglyinterconnect the two elements for the transmissionoi power, as 'disclosed in the copending application entitled Coupling, Serial No. 712,335, filed on even date herewith.

' substantially cylindrical curvature each having While the forms of apparatus herein described constitute preferred embodiments of the invention, it is to be understood that the invention is not limited to these precise forms of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is: a

l. A spring element of the character described comprising a plurality of nested spring shells of an open side and each substantially C-shaped in cross-section, each shell being free to turn with respect to an adjacent shell and free to rub on an adjacent shell throughout substantially its entire extent when the spring element is expanding and contracting.

2. A spring element of the characterdescribedv comprising a plurality of nested spring shells oi substantially cylindrical curvature and of diflerent thicknesses each having an open side and of substantial c-shape in cross-section, each shell having only frictional engagement with an adjacent shell, the thickness of the shells increasing in accordance with the distance of a shell from the central axis.

3. A spring element of the character described I adapted for insertion in a cylindrical passage comprising a plurality of nested spring shells each having an open side and each substantially 0- shaped in cross-section, the ends of each shell v being free to, rub on an adjacent shell when the spring element is expanding and contracting, and a rigid core around which the bight portion of the inner shell is curved, said core having a curved surface with a radius 01. curvature less than the normal "inside radis of curvature of the inner shell.

4. A spring element of the character described comprising a plurality of nested spring shells each having an open side and each substantially c-shaped' in cross section, a rigid core around which the inner shell is curved, and a rib on said core projecting through the openings in the'sides of said shells.

5. A spring element of the character described each having an open side and each curved substantially cylindrically in cross-section, both ends of each shell being free to rub on an adjacent shell when the spring element is expanding and contracting, and a rigid cpre aroundwhich the bight portion of the inner shell is curved. said core having a curved surface with a radius of curvature less than the normal inside radius of curvature of the inner shell.

GUSTAV PIEIBTICK.

CERTIFICATE OF CORRECTION Patent no; 2,059,542.. Ma 5,1936.

GUSTAV PIELSTICK.

' It is herebycertified that error appearsin the printed specification of the above numbered patent requiring correction as follows; Page 1, second column, line 55, forthe word "known" read shown; andthat the said Letters Patent should be read-with this correction therein that the same may conform to the record of the 038s in the Patent Office.

Signed and sesled this 4th of August, A. D. 1936.

Henry V6.11 Airsdale" I Seei) Acting Commissioner of Patents. 

